>Even though the docs say that only 1 index is ever used per
>query, I believe that each JOIN can also make use of an index if it
exists
>(this belief is based on the results of the EXPLAIN(s) of queries
>containing JOINed tables. However, I could be completely wrong in
this
>belief.).

You appear to be right. A query with 2 self-joins on one table uses
both indexes on the table: